A243605 Number of length n+2 0..8 arrays with no three elements in a row with pattern aba (with a!=b) and new values 0..8 introduced in 0..8 order.

4, 10, 29, 97, 366, 1534, 7050, 35166, 188788, 1082913, 6592698, 42315731, 284431573, 1988554321, 14365186163, 106571030511, 807548257486, 6221612919342, 48551842571129, 382621726260959, 3037888284516885

Offset: 1

Author

R. H. Hardin, Jun 07 2014

Keywords

• nonn

Comments

Column 8 of A243607

Examples

			Some solutions for n=5
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....0....0....1....0....1....1....0....1....1....1....1....0....1....0....1
..1....0....1....1....1....2....2....0....2....2....2....2....1....2....1....1
..1....1....2....2....1....0....0....1....3....2....3....2....2....3....1....2
..1....2....3....3....0....1....0....1....1....3....4....1....0....4....1....0
..2....3....1....4....2....3....3....1....0....4....5....3....0....0....0....1
..2....0....1....0....3....4....3....2....4....5....6....3....3....0....0....2
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 30*a(n-1) -365*a(n-2) +2297*a(n-3) -7771*a(n-4) +12461*a(n-5) -2366*a(n-6) -15807*a(n-7) +7237*a(n-8) +10936*a(n-9) -841*a(n-10) -3849*a(n-11) -1625*a(n-12) -307*a(n-13) -28*a(n-14) -a(n-15)